Councillor Ken Pugh, from Swale Borough Council, said he had been campaigning for lighting and speed restrictions since the bridge was opened in 2006.

"If the bridge had been lit properly and speed signs had come up, perhaps the tragedy would not have happened," he added.

Police are still unsure precisely what caused the crash at 7.15am yesterday on the crossing connecting the Isle of Sheppey with mainland Kent.

Chief Inspector Andy Reeves, from Kent Police, told Radio 4’s Today programme: “It’s still the early stages of the investigation. We know clearly it was very thick fog - that is clearly a major factor in the investigation.

“We’re not clear as to the reasons. But we know a vehicle just coming off the bridge back onto the mainland was involved in some kind of collision. Subsequently we had four significant pockets of collisions behind it.”

He added: “I think sometimes people are almost lulled into a false sense of security. If you’re in thick fog, everything is a lot more quiet and muffled. You’re perhaps just watching the lights of the vehicle in front. Well, those lights are going probably at 60 or 70mph, and if they suddenly stop, you need to think, ‘have I got time to react?’”

Witness Martin Stammers, 45, from Minster, said: "It's horrific. I've never seen anything like it in my life.

"All you could hear was cars crashing. We got out of our car and it was eerily quiet, with visibility down to just 20 yards.

He added: "I was very, very, lucky. I was the last car out of it, if you like. As I come to the top of the hill, there were about five cars already smashed up, one was across my carriageway. I had to hit my brakes hard as well, I just had enough space to get through.

"From then on, all you could hear was the screeching of car tyres and the thudding, which was endless. It must have been going on for five to 10 minutes. You could hear hear the screeching, you could hear the lorries thudding into cars, you could hear glass breaking, there was nothing we could do.

"Even after the police turned up, you still heard further down the bridge - a quarter of a mile, half a mile away - cars still going into the back of each other.

"As you went further up, there were cars in the air, there were cars under lorries, there were people laying on the floor, it was just horrendous.”

There were reports of some motorists driving "like idiots" in the conditions before the crash, which completely closed the A249 that goes over the bridge.

Police will look at the lack of lighting on the bridge - a design issue that has been highlighted by the area's Conservative MP Gordon Henderson since it was opened in July 2006.